1. Field of the Invention
This invention relates, generally, to tissue markers. More particularly, it relates to a bioabsorbable marker having an anchoring means that is not bioabsorbable and that is external to the bioabsorbable part of the marker.
2. Description of the Prior Art
Placing a marker in or near a lesion or tumor upon which a biopsy procedure has been performed enables a physician to find the lesion or tumor at a date weeks or months after the biopsy, depending upon the rate of degradation of the marker. The marker may be observed under ultrasound, it may be radiopaque, or the like.
In some cases, the marker material may be completely bioabsorbed by the time the physician needs to locate the lesion or tumor again. One of the ways to enable such re-finding of the lesion or tumor is to attach a metallic marker to the bioabsorbable marker so that the metallic marker may be found by X-ray or other techniques long after the marker has been bioabsorbed.
However, metallic markers are prone to migrate within the tissue. Thus, when they are found after the passage of an extent of time, they may have migrated from their initial position in or near the lesion or tumor, thereby destroying their functionality as a marker to accurately mark the biopsy site.
What is needed, then, is a bioabsorbable marker having a metallic part that does not migrate after the bioabsorbable material of the marker has been absorbed by a patient's body.
However, in view of the prior art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in the pertinent art how the identified need could be fulfilled.